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The environmental analysis and site selection of mussel and large yellow croaker aquaculture areas based on high resolution remote sensing
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作者 Lina Cai Jie Yin +3 位作者 Xiaojun Yan Yongdong Zhou Rong Tang Menghan Yu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期66-86,共21页
Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was propose... Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was proposed and applied to determine the basic environmental characteristics of the best mussel and large yellow croaker aquaculture areas.This methodology includes the first step of extraction of the location distribution and the second step of the extraction of internal environmental factors.The fishery ranching index(FRI1,FRI2)was established to extract the mussel and the large yellow croaker aquaculture area in Zhoushan,using Gaofen-1(GF-1)and Gaofen-6(GF-6)satellite data with a special resolution of 2 m.In the second step,the environmental factors such as sea surface temperature(SST),chlorophyll a(Chl-a)concentration,current and tide,suspended sediment concentration(SSC)in mussel aquaculture area and large yellow croaker aquaculture area were extracted and analyzed in detail.The results show the following three points.(1)For the extraction of the mussel aquaculture area,FRI1 and FRI2 are complementary,and the combination of FRI1 and FRI2 is suitable to extract the mussel aquaculture area.As for the large yellow croaker aquaculture area extraction,FRI2 is suitable.(2)Mussel aquaculture and the large yellow croaker aquaculture area in Zhoushan are mainly located on the side near the islands that are away from the eastern open waters.The water environment factor template suitable for mussel and large yellow croaker aquaculture was determined.(3)This two-step remote sensing method can be used for the preliminary screening of potential site selection for the mussels and large yellow croaker aquaculture area in the future.the fishery ranching index(FRI1,FRI2)in this paper can be applied to extract the mussel and large yellow croaker aquaculture areas in coastal waters around the world. 展开更多
关键词 mussel aquaculture area large yellow croaker aquaculture area high resolution satellite site selection environmental analysis
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Fundamental Ideas and Basic Concepts of HSR Route Selection in Complicated Urban Areas
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作者 WANG Huihuang ZHANG Yiran(Translated) 《Chinese Railways》 2023年第2期53-60,共8页
Up till now,no systematic studies on railway route selection in urban areas,HSR route selection in particular,have been taken in China.Based on the Shenzhen Railway Terminal Project and the Shenzhen-Shanwei Railway Pr... Up till now,no systematic studies on railway route selection in urban areas,HSR route selection in particular,have been taken in China.Based on the Shenzhen Railway Terminal Project and the Shenzhen-Shanwei Railway Project,research on HSR route selection in complicated urban areas has been conducted.An optimal route selection plan is determined after studying the local geological and environmental conditions and the complexity of tunnel construction.The research concludes that there are four major concerns in HSR route selection:the match between the new route and the urban planning,the potential economic return for the massive investment,the likely impacts of land expropriation on social stability,and the best synthesis of multiple controlling factors to meet the HSR standard.Moreover,six principles should be followed in railway route selection in complicated urban areas:the new route should be in alignment with the railway deployment;the route should align with the existing passage as much as possible;extensive analysis and in-depth demonstrations should be done to find the most appropriate combination of open and hidden excavation in tunnel construction;geological conditions and tunnel construction complexities are among the priorities;environmental sensitive sites and environmental vibration noise should be avoided as much as possible;special attention should be paid to the relocation of the power supply,television and communication facilities and the rearrangement of tubes and wires. 展开更多
关键词 high speed railway(HSR) complicated urban areas route selection railway network layout
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Selection of Indigenous Plants in Roads in Northwestern Loess Plateau Area
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作者 张铁军 王春玲 《Agricultural Science & Technology》 CAS 2012年第3期583-591,共9页
[Objective] The aim was to study on resource utilization of indigenous plants in roads in order to solve resource shortage of indigenous plant in bioengi- neering. [Method] Based on northwestern loess plateau area, we... [Objective] The aim was to study on resource utilization of indigenous plants in roads in order to solve resource shortage of indigenous plant in bioengi- neering. [Method] Based on northwestern loess plateau area, we conducted research on selection of indigenous plants and survey on the species which could live in adverse condition, mainly by surveying, with frequent tests as a supplement, to make a comprehensive observation and evaluation on plant combinations which are to be extensively applied. [Result] The research indicated that in central dividing strips, four arbors, including Platycladus orientalis (Linn.)Franco, Sabina chinensis, Sabinachinen- sis(Linn.)Ant., and Ulmus purnila L., and nine frutices, including Lycium chinense, Tamarix austromongolica, Rosa xanthina Lindl., Forsythia suspense, Atriplex canescens, Amygdalus triloba, Hippophae rharnnoides Linn., Arnorpha fruticosa L., and Syzygium aromaticum could be planted. In addition, Gleditsia sinensis Lain, Robinia pseudoacacia L, Elaeagnus angustifolia L., Rhus typhina, Salix babylonica, Salixmatsudana and Fraxinus chinensis, tall and strong, are suitable to be planted as border trees, presenting a good vision. Frutices, limited by height, are usually with more branches, which will provide a good landscape if grown with tall plants. Prunus dacidiana and Ulmus pumila L., prone to be damaged by insects, should be planted with other species to stop the infestation in space. [Conclusion] The research laid foundation for selection of indigenous plants in roads, providing references for resource shortage of indigenous plant for bioengineedng. 展开更多
关键词 Loess Plateau area ROAD Indigenous plant selection Plant combination
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Engineering Geological Assessment for Route Selection of Railway Line in Geologically Active Area:A Case Study in China 被引量:1
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作者 HUANG Run-qiu LI Yan-rong +1 位作者 QU Ke WANG Ke 《Journal of Mountain Science》 SCIE CSCD 2013年第4期495-508,共14页
The Cheng-Lan railway links Chengdu, a central city in Southwestern China, and Lanzhou, a central city in Northwestern China. The railway passes through the Longmenshan fault zone (Wenchuan earthquake happened there o... The Cheng-Lan railway links Chengdu, a central city in Southwestern China, and Lanzhou, a central city in Northwestern China. The railway passes through the Longmenshan fault zone (Wenchuan earthquake happened there on May 12, 2008), Minjiang fault zone, and Dongkunlun fault zone, which are all active. It runs over the Yangtze River and the Yellow River, and crosses high mountains and deep valleys. There exists, along the railway's alignment, different kinds of strata of hard granite and soft, weak metamorphic rocks such as carbonaceous slate, schist, and phyllite. It is, therefore, a key issue for such an infrastructure construction to assess the engineering geological conditions and risks, so as to mitigate or avoid possible georisks and to offer optional designs. Geological survey and georisk assessment along the railway corridor are carried out. Special attention is given to active faults, earthquakes and seismic zones. Based on these, discussions about geological aspects for route selection of the railway are conducted and countermeasures for georisk control are proposed accordingly. Main conclusions are achieved as follows: (1) Geohazards such as landslides, rockfalls and debries flows dominate both the route selection of the railway and the engineering structures (e.g., tunnels or bridges) adopted; (2) Tunnel has been proved to be an excellent structure for linear engineering in geologically active area; and (3) In the case where avoiding is impractical, necessary protection measures should be taken to engineering slopes in high earthquake intensity areas, especially the area with earthquake of Ms. 8 or greater. 展开更多
关键词 Railway route selection Geologicallyactive area EARTHQUAKE Active fault
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Selection of organic Rankine cycle working fluid based on unit-heat-exchange-area net power 被引量:1
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作者 郭美茹 朱启的 +2 位作者 孙志强 周天 周孑民 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1548-1553,共6页
To improve energy conversion efficiency, optimization of the working fluids in organic Rankine cycles(ORCs) was explored in the range of low-temperature heat sources. The concept of unit-heat-exchange-area(UHEA) net p... To improve energy conversion efficiency, optimization of the working fluids in organic Rankine cycles(ORCs) was explored in the range of low-temperature heat sources. The concept of unit-heat-exchange-area(UHEA) net power, embodying the cost/performance ratio of an ORC system, was proposed as a new indicator to judge the suitability of ORC working fluids on a given condition. The heat exchange area was computed by an improved evaporator model without fixing the minimum temperature difference between working fluid and hot fluid, and the flow pattern transition during heat exchange was also taken into account. The maximum UHEA net powers obtained show that dry organic fluids are more suitable for ORCs than wet organic fluids to recover low-temperature heat. The organic fluid 1-butene is recommended if the inlet temperature of hot fluid is 353.15-363.15 K or443.15-453.15 K, heptane is more suitable at 373.15-423.15 K, and R245 ca is a good option at 483.15-503.15 K. 展开更多
关键词 organic Rankine cycle(ORC) working fluid selection net power heat exchange area
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Spatial pattern recognition for near-surface high temperature increases in mountain areas using MODIS and SRTM DEM
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作者 WANG Yanxia YANG Lisha +1 位作者 HUANG Xiaoyuan ZHOU Ruliang 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2025-2042,共18页
Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are n... Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are necessary but highly difficult due to the complicated environmental conditions and instrumental issues.This paper develops a spatial pattern recognition method to measure the near-surface high temperature increase(NSHTI),one of the lesser-attended changes.First,raster window measurement was proposed to calculate the temperature lapse rate using MODIS land surface temperature and SRTM DEM data.It fully considers the terrain heights of two neighboring cells on opposite or adjacent slopes with a moving window of 3×3 cell size.Second,a threshold selection was performed to identify the NSHTI cells using a threshold of-0.65℃/100 m.Then,the NSHTI strips were parameterized through raster vectorization and spatial analysis.Taking Yunnan,a mountainous province in southwestern China,as the study area,the results indicate that the NSHTI cells concentrate in a strip-like pattern along the mountains and valleys,and the strips are almost parallel to the altitude contours with a slight northward uplift.Also,they are located mostly at a 3/5 height of high mountains or within 400 m from the valley floors,where the controlling topographic index is the altitude of the terrain trend surface but not the absolute elevation and the topographic uplift height and cutting depth.Additionally,the NSHTI intensity varies with the geographic locations and the proportions increase with an exponential trend,and the horizontal width has a mean of about 1000 m and a maximum of over 5000 m.The result demonstrates that the proposed method can effectively recognize NSHTI boundaries over mountains,providing support for the modeling of weather and climate systems and the development of mountain resources. 展开更多
关键词 High temperature increase Mountain areas MODIS Spatial pattern recognition Raster window measurement Threshold selection
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Study on Selection of Dust Collectors for Large Capacity Thermal Power Units in High Altitude Areas
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作者 Wen Yiqian Cao Hongzhen Qi Jinsheng 《Meteorological and Environmental Research》 CAS 2017年第3期62-66,共5页
A dust collector is an important equipment in a thermal power plant,and reasonable selection of a dust collector is important for environmental protection in the power plant. Huaneng Xining Power Plant is located at a... A dust collector is an important equipment in a thermal power plant,and reasonable selection of a dust collector is important for environmental protection in the power plant. Huaneng Xining Power Plant is located at an elevation of 2 360 m. Based on the characteristics of the high altitude area and their special requirements for dust collectors,the selection of dust collectors for the thermal power unit in the high altitude area was studied,and then two types of dust collectors( a rotary electrode electrostatic precipitator and electric-bag composite precipitator) for the thermal power unit were compared from the aspects of technological and economical feasibility. Finally,a proposal to select a suitable dust collector for the thermal power plant was put forward. 展开更多
关键词 High ALTITUDE areas ROTARY electrode ELECTROSTATIC PRECIPITATOR Electric-bag composite PRECIPITATOR selection of DUST collectors
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Construction of Silk Road Economic Belt and Industrial Selection of Minority Areas in Northwest China
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作者 HE Aihong WANG Yilong 《Journal of Landscape Research》 2016年第4期73-76,81,共5页
Construction of Silk Road Economic Belt is a giant engine for the economic upgrading of China.Minority areas in Northwest China since then has become a forward position for the opening to the west,which is extremely s... Construction of Silk Road Economic Belt is a giant engine for the economic upgrading of China.Minority areas in Northwest China since then has become a forward position for the opening to the west,which is extremely significant for expanding the hinterland of Chinese economic development,activating economic development in inland and border areas,promoting the open economic development in central and west China,and also forming a new growth pole of Chinese economy.Optimization of industrial selection can promote economic development,constant economic growth of the northwest minority areas and the construction of Silk Road Economic Belt requires the optimization and adjustment of industrial selection,cultivation of competitive industries with market prospects,and formation of new economic growth points.Minority areas in northwest China have a vast territory and abundant resources that are all powerful support for the development of local competitive industries. 展开更多
关键词 Silk Road Economic Belt CONSTRUCTION Northwest minority areas Industrial selection
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Selection Experiment of Varieties of Maize in Ailao Mountainous Areas
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作者 方绍军 《Agricultural Science & Technology》 CAS 2017年第11期2082-2084,2087,共4页
[Objective] This study aimed to select suitable varieties of maize for Ailao mountainous areas, [Method] A comparison test of eight varieties of maize was conducted in Shengli Village, Mosha Town, Xinping County, Yunn... [Objective] This study aimed to select suitable varieties of maize for Ailao mountainous areas, [Method] A comparison test of eight varieties of maize was conducted in Shengli Village, Mosha Town, Xinping County, Yunnan Province from May to October in 2016. [Result] The yield of Shenyu 10 was up to 66.3.4 kg/ 667 m^2 and there were extremely significant differences between Shenyu 10 and Xuanhuangdan 5 (CK). Moreover, it had strong stress resistance. As Jingdan 12, Beiju 0913, Ante 8000, Yunrui 89 and Yayu 78 were planted in the region, their earing should not appear in rainy months. The inciderce of stem rot and ear rot of Yayu 891 was high, so Yayu 891 should not be planted in the region. [Conclusion] Shenyu 10 had a high yield, suffered few diseases and had strong stress resistance, so it can be popularized widely in the region. 展开更多
关键词 MAIZE selection of varieties Ailao mountainous areas Xinping County of Yunnan Province
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WCDMA Outdoor Antenna Selection for Dense Urban Areas
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作者 Lu Tongjiu, Sun Huixia, Wanglijun (Mobile Division of ZTE Corporation, Shanghai 201203, China) 《ZTE Communications》 2005年第1期27-29,共3页
Interference control can be realized by selecting the antenna' s electrical and engineering parameters such as gain and radiation pattern, height, azimuth and downtilt to directly influence the field intensity dis... Interference control can be realized by selecting the antenna' s electrical and engineering parameters such as gain and radiation pattern, height, azimuth and downtilt to directly influence the field intensity distribution of radio signals and effectively and reasonably distribute the electro-magnetic energy. This paper discusses how to select an antenna for a densely populated urban area. The discussion is based on the simulation platform of ZTE ' s WCDMA planning system. 展开更多
关键词 WCDMA Outdoor Antenna selection for Dense Urban areas ZTE
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Path Selection of Xi'an Free Trade Area Construction under the Strategy of Silk Road Economic Belt
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作者 CHEN Weifeng 《International Journal of Technology Management》 2016年第1期7-9,共3页
From the present situation of worldwide flee-trade area and the new trend of reform and opening in China after 18 of the fifth plenary session, you can see that in domestic, the construction and development of free-tr... From the present situation of worldwide flee-trade area and the new trend of reform and opening in China after 18 of the fifth plenary session, you can see that in domestic, the construction and development of free-trade area, taking regional core city as center, is economy transformation means under new normal economic environment, and new clues to improve the level of reform and opening. The establishments of free trade Area in Shanghai, Guangdong, Tianjin, Fujian provided references for establishing a free trade area of xi ' an under the background of the silk road economic belt construction. This article firstly analyzes the present domestic and foreign research situation and development trend; and then put forward the necessity of building Xi' an free trade area. Then discusses the Xi' an Silk Road economic belt free trade area construction strategy. Finally, in combination with the practical situation of Xi' an, it proposes path selection of Xi' an free trade area construction under the strategy of Silk Road economic belt. 展开更多
关键词 Silk Road Economic Belt Xi' an Free Trade area Path selection
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1.5μm Self-Aligned Spotsize Converter Integrated DFB Fabricated by Selective Area Grown MOVPE
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作者 邱伟彬 董杰 +1 位作者 王圩 周帆 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第7期681-684,共4页
High performance 1 57μm spotsize converter monolithically integrated DFB is fabricated by the technique of self aligned selective area growth.The upper optical confinement layer and the butt coupled tapered thickn... High performance 1 57μm spotsize converter monolithically integrated DFB is fabricated by the technique of self aligned selective area growth.The upper optical confinement layer and the butt coupled tapered thickness waveguide are regrown simultaneously,which not only offeres the separated optimization of the active region and the integrated spotsize converter,but also reduces the difficulty of the butt joint selective regrowth.The threshold current is as low as 4 4mA.The output power at 49mA is 10 1mW.The side mode suppression ratio (SMSR) is 33 2dB.The vertical and horizontal far field divergence angles are as small as 9° and 15° respectively,the 1dB misalignment tolerance are 3 6μm and 3 4μm. 展开更多
关键词 spotsize converter self aligned butt joint selective area growth
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Selective Area Growth and Characterization of GaN Nanorods Fabricated by Adjusting the Hydrogen Flow Rate and Growth Temperature with Metal Organic Chemical Vapor Deposition 被引量:1
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作者 任鹏 韩刚 +6 位作者 付丙磊 薛斌 张宁 刘喆 赵丽霞 王军喜 李晋闽 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第6期145-149,共5页
CaN nanorods are successfully fabricated by adjusting the flow rate ratio of hydrogen (H2)/nitrogen (N2) and growth temperature of the selective area growth (SAG) method with metal organic chemical vapor deposit... CaN nanorods are successfully fabricated by adjusting the flow rate ratio of hydrogen (H2)/nitrogen (N2) and growth temperature of the selective area growth (SAG) method with metal organic chemical vapor deposition (MOCVD). The SAG template is obtained by nanospherical-lens photolithography. It is found that increasing the flow rate of 1-12 will change the CaN crystal shape from pyramid to vertical rod, while increasing the growth temperature will reduce the diameters of GaN rods to nanometer scale. Finally the CaN nanorods with smooth lateral surface and relatively good quality are obtained under the condition that the H2:N2 ratio is 1:1 and the growth temperature is 1030℃. The good crystal quality and orientation of GaN nanorods are confirmed by high resolution transmission electron microscopy. The cathodoluminescence spectrum suggests that the crystal and optical quality is also improved with increasing the temperature. 展开更多
关键词 of or IS as RATE GAN selective area Growth and Characterization of GaN Nanorods Fabricated by Adjusting the Hydrogen Flow Rate and Growth Temperature with Metal Organic Chemical Vapor Deposition by with
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A Comparative Study on the Selected Area Electron Diffraction Pattern of Fe Oxide/Au Core-shell Structured Nanoparticles
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作者 Qianghua LU Kailun YAO +3 位作者 Dong XI Zuli LIU Xiaoping LUO Qin NING 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2007年第2期189-192,共4页
The selected area electron diffraction (SAED) pattern of magnetic iron oxide core/gold shell nanoparticles has been studied. For the composite particles with mean size less than 10 nm, their SAED pattern is found to... The selected area electron diffraction (SAED) pattern of magnetic iron oxide core/gold shell nanoparticles has been studied. For the composite particles with mean size less than 10 nm, their SAED pattern is found to be different from either the pattern of pure Fe oxide nanoparticles or that of pure Au particles. Based on the fact that the ring diameters of these composite particles fit the characteristic relation for the fcc structure, the Au atoms on surfaces of the concerned particles are supposed to pack in a way more tightly than they usually do in pure Au nanoparticles. The driving force for this is the coherency strain which enables the shell material at the heterostructured interface to adapt the lattice parameters of the core. 展开更多
关键词 Core-shell structured nanoparticles Magnetic Fe oxide selected area electron diffraction Biological applications
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Phase Identification Using Series of Selected Area Diffraction Patterns and Energy Dispersive Spectrometry within TEM
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作者 Kun-Lin Lin 《Microscopy Research》 2014年第4期57-66,共10页
Transmission electron microscopy (TEM) is a very powerful technique for materials characteriza-tion, providing information relating to morphology, composition, and crystal structure. Selected area diffraction patterns... Transmission electron microscopy (TEM) is a very powerful technique for materials characteriza-tion, providing information relating to morphology, composition, and crystal structure. Selected area diffraction patterns (SADPs) are crystallographic data that can be obtained using a TEM in-strument. Conventional identification through SADP/TEM is tricky and tedious, thereby increasing the difficulty of phase identification. To establish a procedure for phase identification of known and unknown phases, in this study we examined two samples: one, a known phase, was Si with alignment;the other, unknown, was the TixOy phase at the 96.4Au-3Ni-0.6Ti interlayer/ yttria-stabilized zirconia (YSZ) interface of a steel/96.4Au-3Ni-0.6Ti interlayer/YSZ joint. The procedures for phase identification of the known and unknown phases are described herein using a series of SADPs and energy dispersive spectrometry within TEM that would be useful for general researchers. 展开更多
关键词 Phase Identification Transmission Electron MICROSCOPY selectED area DIFFRACTION Pattern Energy DISPERSIVE Spectroscopy
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Fabrication of 32 Gb/s Electroabsorption Modulated Distributed Feedback Lasers by Selective Area Growth Technology
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作者 周代兵 王会涛 +8 位作者 张瑞康 王宝军 边静 安欣 陆丹 赵玲娟 朱洪亮 吉晨 王圩 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第5期66-68,共3页
A 32 Gb/s monolithically integrated electroabsorption modulated laser is fabricated by selective area growth technology. The threshold current of the device is below 13mA. The output power exceeds 10mW at 0V bias when... A 32 Gb/s monolithically integrated electroabsorption modulated laser is fabricated by selective area growth technology. The threshold current of the device is below 13mA. The output power exceeds 10mW at 0V bias when the injection current of the distributed feedback laser is 100mA at 25℃. The side mode suppression ratio is over 50 dB. A 32Gb/s eye diagram is measured with a 3.SVpp nonreturn-to-zero pseudorandom modulation signal at -2.3 V bias. A clearly opening eyediagram with a dynamic extinction ratio of 8.01 dB is obtained. 展开更多
关键词 Fabrication of 32 Gb/s Electroabsorption Modulated Distributed Feedback Lasers by selective area Growth Technology EML EAM DFB InGaAs SAG
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Selective Area Growth of GaAs in V-Grooved Trenches on Si(001) Substrates by Aspect-Ratio Trapping
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作者 李士颜 周旭亮 +5 位作者 孔祥挺 李梦珂 米俊萍 边静 王伟 潘教青 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期148-151,共4页
A high quality of GaAs crystal growth in nanoscale V-shape trenches on Si(O01) substrates is achieved by using the aspect-ratio trapping method. GaAs thin films are deposited via metal-organic chemical vapor deposit... A high quality of GaAs crystal growth in nanoscale V-shape trenches on Si(O01) substrates is achieved by using the aspect-ratio trapping method. GaAs thin films are deposited via metal-organic chemical vapor deposition by using a two-step growth process. Threading disJocations arising from lattice mismatch are trapped by laterally confining sidewalls, and antiphase domains boundaries are completely restricted by V-groove trenches with Si { 111} facets. Material quality is confirmed by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high resolution X-ray diffraction. Low temperature photoluminescence (PL) measurement is used to analyze the thermal strain relaxation in GaAs layers. This approach shows great promise for the realization of high mobility devices or optoelectronie integrated circuits on Si substrates. 展开更多
关键词 selective area Growth of GaAs in V-Grooved Trenches on Si Substrates by Aspect-Ratio Trapping
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Migrants Selectivity and the Effects on Environmental-Induced Migration Project in Sanjiangyuan Area in China
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《Sociology Study》 2012年第3期159-167,共9页
Sanjiangyuan Area is located in Tibetan Plateau in Qinghai Province in China. It's the source of Yangtze River, Huanghe River and Lancangiiang River. Since the ecological environment became worse in recent decades, Q... Sanjiangyuan Area is located in Tibetan Plateau in Qinghai Province in China. It's the source of Yangtze River, Huanghe River and Lancangiiang River. Since the ecological environment became worse in recent decades, Qinghai government conducted an environmental migration project to move the herdsman out of Sanjiangyuan Area to protect the environment. Using the data we collected in five environmental migration resettlement villages in 2009 and the basic information of the nonmigrants, this paper calculated the index of migration differences to examine the selectivity between migrants and nonmigrants. The policy implication will also be discussed in this paper. 展开更多
关键词 Environmentalinduced migration migrants selectivity Sanjiangyuan area
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Optimization of Green Space Plant Configuration in Residential Areas of Chongqing Central Business District Based on Green Plot Ratio—A Case Study of Xuhui City Residential Community
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作者 Xianteng Ma Tinghan Yan +2 位作者 Yangyang Qin Haoli Wang Yifan Yan 《Journal of Geoscience and Environment Protection》 2023年第6期37-49,共13页
The current urban green space construction was guided by a two-dimensional index evaluation system, resulting in weak ecological benefits of green space. Green plot ratio (GPR), as a three-dimensional indicator, can c... The current urban green space construction was guided by a two-dimensional index evaluation system, resulting in weak ecological benefits of green space. Green plot ratio (GPR), as a three-dimensional indicator, can characterize the ecological benefits of green areas and the ability of green areas to participate in the operation and regulation of urban ecosystems. As an important component of urban green space, the GPR index was added to the two-dimensional index evaluation system to optimize the green space, which can promote the development of low-carbon, healthy and ecological green space. Based on the research of 22 residential districts in the central city of Chongqing, the Leaf area index (LAI) index of common native garden plants in Chongqing was formed to improve the accuracy of green capacity index measurement in Chongqing. The study also took the residential community of Sunrise City in Banan District of Chongqing as an example, and carried out the optimization design practice from four types of residential community green areas: green areas next to houses, road green areas, concentrated green areas, and green areas attached to public service facilities. 展开更多
关键词 Urban Greening Ecological Benefits Residential District Leaf area Index Plant selection
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民勤荒漠区油莎豆种质资源筛选研究 被引量:2
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作者 康才周 朱淑娟 +3 位作者 安红燕 王家奇 姜生秀 张德魁 《安徽农业科学》 CAS 2024年第11期19-23,共5页
[目的]筛选出适宜在民勤荒漠区推广种植的高产高油油莎豆,对民勤产业发展具有重要的战略意义。[方法]引入10个不同种质资源油莎豆,观测其出苗率,测量产量和油脂含量,同时运用SPSS软件对比分析不同种源地油莎豆种质资源的产量、油酸含量... [目的]筛选出适宜在民勤荒漠区推广种植的高产高油油莎豆,对民勤产业发展具有重要的战略意义。[方法]引入10个不同种质资源油莎豆,观测其出苗率,测量产量和油脂含量,同时运用SPSS软件对比分析不同种源地油莎豆种质资源的产量、油酸含量,以及人体不能合成而必须从膳食中补充的亚油酸和亚麻酸含量。[结果]不同种源地油莎豆种质资源之间产量有差异;不同种源地油莎豆种质资源之间油酸、亚油酸含量差异显著;引入的10个不同种源地油莎豆种质资源中,出苗率均超过90%,产量均超过6000.0 kg/hm^(2),其中有4个油莎豆种质资源的油酸含量位于最佳食用油脂肪酸组成区间,其亚油酸和亚麻酸含量由高到低排序为河南油莎豆、西班牙油莎豆、中科院油莎豆6号、武汉1号。[结论]适宜在民勤荒漠区推广种植的高产高油油莎豆种质资源依次为河南油莎豆、西班牙油莎豆、中科院油莎豆6号和武汉1号。 展开更多
关键词 油莎豆 种质资源 筛选 荒漠区 推广
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